The invention relates to a fuel tank for a motor vehicle having a plurality of surge chambers for collecting fuel, having a plurality of fuel pumps for feeding fuel from the surge chambers to an internal combustion engine of the motor vehicle and for feeding fuel to suction jet pumps arranged in the fuel tank, and having feed lines for the suction jet pumps for feeding fuel into the surge chambers.
Fuel tanks of this type are frequently used in particular for high-power motor vehicles, in which a single feed unit having a surge chamber and a fuel pump can be difficult to arrange in the fuel tank due to its excessive dimensions because of the power values, and are known from practice. In this case, the fuel pumps generally have a preliminary stage for feeding the fuel from the fuel tank directly into the surge chamber and a main stage for feeding the fuel from the surge chamber to the internal combustion engine, and are arranged within the surge chamber. In addition, fuel is frequently returned into the surge chambers by a pressure regulator in the form of a return controlling means. This design has the advantage that the surge chambers are filled in a number of ways.
It is disadvantageous, however, that the suction jet pumps are continuously supplied with fuel by the fuel pumps. This leads to an unnecessary circulation of fuel and therefore to a high permeation of fuel out of the fuel tank. Furthermore, the continuous circulation of the fuel leads to the formation of gas bubbles in the fuel and therefore to an impairment of the fuel feed.
Consideration has already been given to controlling the surge chambers with float valves, so that, if a surge chamber is filled, no more fuel is conducted out of the return into this surge chamber. However, the fuel tank becomes very complex in terms of design and susceptible to faults as a result.
The invention is based on the problem of designing a fuel tank of the type mentioned at the beginning in such a manner that an unnecessary circulation by the suction jet pumps is largely avoided.